Adding flange to curved sheet metal

saba_nikkhah166

I need to add some flanges to a sheet metal model which is bent in a 290mm radius (something like the image below). As I need the flat pattern model I should be adding the flanges before I finish the sheet metal.  Is there any additional feature or solution to the problem?

pmd

@saba_nikkhah166 it is not possible to add a flange to a curved edge. I believe this is because the underlying Onshape model of sheet metal is constant thickness and a flange on a curved edge would imply some stretching or compression so is simply not possible even though very common for thin-gauge sheet metal in the real world...

The only workaround I can think of is to change the curved sheet to a series of flats and then put a flange on each of the now linear edges:  https://cad.onshape.com/documents/1c54e2e623524effe86008f1/w/8474c83ed00cd1b971cd8e85/e/f80e20141d02d27cf1491814

This is pretty ugly and the flat pattern will now have the wrong size for an actual rolled sheet.

glen_dewsbury

I've done a few for fuel tanks by the segmented method you're showing and they don't look ugly to me. I don't try to roll them at all, that would get ugly unless you've got custom flanging tools. Using all straight bends and cleoco holes to assembly the closed aluminum tanks for welding does a nice job.